My invention relates to a method of treating finely divided materials in which an apparatus is employed with a treatment fluid, particularly for conditioning oil containing vegetable raw materials, comprising one or more vibratory conveyors with a perforated bottom and at least one inlet opening under the perforated bottom, for introducing a treatment fluid.
Such a device for treating finely divided materials with gaseous media, e.g. for drying sugar, is known per se. In order to prevent in this known device the perforated bottom from becoming obstructed, when drying materials, said bottom is covered for example with flexible sheets, whereby incrustation of the transport surface is avoided.
Though this device is suitable for preventing incrustation it can not be used to pulverize sufficiently the lumps produced by clotting. This is a considerable disadvantage when pre-treating oil containing vegetable raw materials, while moreover the difficulty is met that during the steam treatment in the first stage of the treatment of oil containing vegetable raw materials, clotting of the pulverized oil containing vegetable raw materials occurs. These clots of material cannot be dried in the normal drying time and constitute, after normal drying, an untreatable product.
Clotting and adherence of the raw material to the bottom of a vibrator conveyor is substantially produced in the first stage of heating and humidifying the pulverized oil containing vegetable raw materials. Clots pulverized after this stage do not show these symptoms when they are further heated and exposed to the effect of steam for humidification. When the treatment is performed under the right circumstances, the already partially pre-treated oil containing raw material has moreover after humidification, still sufficient agglomerating properties to bind the dust meanwhile formed during pulverization, so that a product with excellent extraction properties is obtained.
Since the structure of the raw material after it has passed through the first stage of thermal treatment, that is to say: heating and humidification by means of steam, has been changed such that already on minor pressure oil issues, whereby balls form which cannot be treated any further, pulverization should be performed with great care.